Concrete mixing plant



April 15, 1941.- A. w. RYBECK ETAL 2,238,343

CONCRETE MIXING PLANT Fil ed Feb. 19, 1937 2 sheets-sht 1 Ada/pl? Mfiybeak flag M HUJ/E April 15, 1941. A. w. RYBECK ETAL 2,238,343

CONCRETE MIXING PLANT Filed Feb. 19, 1937 2 Sheets-Sheet 2 Patented Apr. 15, 1941 CONCRETE MIXING PLANT Adolph w. Rybeck and-Roy M. Hoya, Milwaukee,

Wis., assignors to T. L. Smith Company, Milwaukee, Wis., a corporation of Wisconsin Application February 19, 1937, Serial No. 126,680

4 Claims.

This invention relates to concrete mixers and refers particularly to concrete mixing plants of the type usually erected at large projects for continuous operation over comparatively long periods of time. I

In plants of this character a battery of mixers is employed, all of which are fed from a common supply bin, and usually a single hopper receives the mixed concrete to conduct it into transit trucksor onto chutes for conveyance directly to the pouring location.

Heretofore, these plants have been so constructed that the several mixers employed were loaded at one end and discharged from the opposite end of their drums, and as the mixers usually employed in plants of this character are quite large, their charging openings were necessarily widely separated. This wide separation of th charging openings, together with the fact that the aggregates come from a central source, required a high elevation for the material supply bin and the batching or measuring hopper to obtain the proper flow of aggregates, into the mixers.

Obviously, any factors which require an increase in the overall height of the Plant are objectionable, and it is therefore an object of this invention to reduce the overall height of a concrete mixing plant through a new and novel arrangement of the mixers.

More specifically it is. an object of this invention to provide an improved manner of loading or charging a battery of concrete mixers from a central source so that the aggregates have a short substantially straight path from the central source directly to any selected mixer.

Another object of this invention is to so-arrange a battery of tilting drum mixers of the type in which one end of the drum provides both the charging and the discharging opening, that all of the drums discharge into a common hopper and have their combined charging and discharging ends located in juxtaposition to a source of supply from which the aggregates may be directly chuted into any one selected mixer.

Another object of this invention is to group a plurality of concrete mixers of the type described about a common vertical axis and to provide a rotatable spout fed from a measuring or batching hopper and movable into alignment with any selected mixer to direct the aggregates thereto.

Another object of this invention is to provide a movable chute for each mixer arranged so as to conduct the aggregates directly into the drum" v and of the mixer and to swing out'of the path of the drum as it tilts to discharge its contents.

With the above and otherobjects in view which will appear as the description proceeds, this invention resides in the novel construction, combination and arrangement of parts substantially as hereinafter described and more particularly defined by the appended claims, it being understood that such changes in the precise embodiment of the hereindisclosed invention may be made as come within the scope of the claims.

The accompanying drawings illustrate one complete example of the physical embodiment of the invention constructed according to the best mode so far devised for the practical application of the principles thereof, and in which:

Figure 1 is a side view of a concrete mixing plant embodying this invention;

Figure 2 is an enlarged side view of the mixers showing their relationship to each other and to the supply bin and concrete receiving hopper, parts thereof being broken away and in section;

Figure 3 is an end view of one of the mixers;

Figure 4 is a top view of four mixers illustrating the manner in which they are grouped about a common center.

Referring now particularly to the accompanying drawings in which like numerals indicate like parts throughout the several views, the numeral 5 designates the fabricated framework of the mixing plant. At its top the framework supports a supply bin 8, which, as is customary in plants of this character, is partitioned to provide separate compartments for the different materials which are elevated thereto by conveyors (not shown). Beneath the supply bin 8 is' a measuring or batching hopper 9 into which the different materials of the aggregate flow from the supply bin 8. The measuring or batching hopper 9 properly proportions the materials and discharges the aggregate from a central discharge Ill.

The battery of mixers H is mounted on a floor l2 preferably located at an elevation permitting transit trucks or other vehicles l3 to be driven thereunder. The mixers are grouped about a central concrete receiving hopper M which has its open top at the level of the floor I2 so that the several mixers may discharge their contents directly into it. From the hopper 14, the concrete flows into a waiting transit truck 13 or onto a chute (not shown) for conveyance directly to the pouring location.

The mixers H are of the tilting drum'type in which the drum I5 is rotatably hung or supported in a cradle l6 which is pivotally supported as at I! (see Figure 3) between upright pedestals l8. The motor or other driving unit l9, indicated in dotted lines in Figure 3, is carried by the tilting cradle so that the driving connection between it and the ring gear 20 of the drum is at all times maintained even as the drum is tilted. Power actuated tilting mechanism 2| is preferably provided to tilt the drum.

Inasmuch as the specific construction of the mixers does not actually form a part of this invention, a detailed description thereof is unnecessary and for such description reference may be had to Patent No. 2,054,469, issued-to Adolph W. Rybeck September 15, 1936.

It is important to note, however, that. these mixers while capable of being. charged from either end are essentially the so-called front end charging mixers. and discharged at the same end of thedrum.

-Regardless of the number of mixers in the battery, whether it is two, as shown in Figures 1 and 2; or four, as shown in'Figure 4, or any other convenient-number, they are'grouped about the Vertical axis of the concrete receiving hopper M which is also common to the discharge ID of the measuring or batching hopper 9. It is preferable that the mixers be so mounted that the axes of their drums intersect this common vertical axis i so that each mixer discharges. properly into the hopper l4.

"Each mixer has a supply chute 22 arranged to conduct-materialintotheopen front end of the drum when the drum'is in its charging position.

' This supply chuteis pivotedas at 23'from acentral support 24-suspended I from asupporting structure 25 carried by theiramework of the plant. The pivotal'mounting of the chute 22 permits it to'be swung from a charging position to a positionclear of the mixer to allow unrestricted discharge of the drum contents.

-Aconnection between the chute and the cradle which carries the drum swings the chute automaticallyto its position clear of the drum. as it is tilted'to dischargingposition and returns it to its proper charging position when the drum is tilted back to.loading position. "This connection comprises a rigid bracket 25 carried by the cradle .and a link 2! connecting the outer .end thereof,

with the chute.

I Rotatably mounted. beneath the discharge l ofthe measuring or batching hopper is a spout 28. Being rotatably mounted, the spout 28 is selectively positionable, over-any one of" the supply chutes Z2 to conduct: material'from the hopper. 9 directlygintoi'the selected chute.

.Measured quantities of water are conducted into the drum along with the aggregates froma funnel-like receptacle 29 encircling the spout 28' enter the drum at higher velocity since the flow is almost in a straight downward line.

Another advantage of this invention which will be readily apparent to those skilled in the art, and which contributes to efiect a faster charging cycle, is that the automatically operated feed chutes seal their drum openings and permit the rotatable spout to be moved into alignment with the-next mixer immediately after the: charging operation is a completed.

What we claim as our invention is:

1. In a concrete mixer: a rotatable mixing drum having a common charging and discharging opening at one end; a tilting cradle mountingthe drum; for-.endwise tilting movement from a charging-to a discharging position; a supply In other words, they are'charged .ingcycleisalso made possible as the aggregates chute for. conducting material into the combined charging and discharging opening of the drum; means pivotally mounting the receiving end of the'supply chute so that its discharging end is .movable from a position directing materials into said endof the drum" to' a posi'tion clear of said cnd of the'drum and 'an" operative connection betweenthe cradle and the supply chute for supporting the discharge end of the chute, said con- .said'discharge. opening rotatable about saidvertical axis todire'ctaggregates toward any one selected mixer; an individual chute for eachmixer arranged to conduct material from the spout into the drum of its respective mixer; and means independently of the. drum for moving the. chute of each mixer into and out of operative position by tilting of themixer drum to its chargingand discharging positions respectively.

3. A concrete mixing plant comprising: a central concrete receiving hopper; a.-plurality of mixers of, the tilting drum type.that..may be charged and dischargedatthe same .end;..said mixers being mounted above the. concrete receiving hopperand groupdabout. the vertical .axis of the central concrete receiving hopper with the combined charging and discharging ends of their drums facing said' axis so that all of said mixers may discharge into said central concretereceiving hopperyan aggregate'supply hopper above the mixershaving adis'charge' opening substantially on said vertical axis; a spout beneath said discharge opening, said spout being rotatable about said'vertical axis todire'ct material to- 'ward: any one-ofrthe mixers; a supply chute for each mixer; means hingedlymounting each chute 'for bodily movementfrom ajposition atwhich it conducts material from the spout-into the'drum of its respective'mixer'to' aposition clearzof the :mixer drum; andmeans independent of the =drumsoperable by the tilting'ofthe'mixer drums forautomatically:swinging their chutes to inop- -erative positions: clear of the drums' as the drums are tilted to discharging'positions;.and for swinging-the :chutesto their :operative positions'for conducting :material .1 from lithe spout into the drums as the drums are ."tiltedi to'ftheir. mixing positions.

4. A concrete mixing plant comprising: at least two mixers of the tilting drum type that may be charged and discharged at the same end; a concrete receiving hopper beneath said mixers; an aggregate supply hopper above the mixers having a discharge opening substantially in vertical alignment with the concrete receiving hopper; means mounting the mixers for rotation on an axis such that their combined charging and discharging ends point toward the substantially common vertical axis of the receiving and supply hoppers so that each mixer may discharge into the receiving hopper, said means also mounting 'the mixers for tilting motion from mixing positions in which their combined charging and discharging ends point toward the supply hopper to discharging positions at which their combined positions during tilting of the drums from mixing positions to discharging positions respectively. ADOLPH W. RYBECK. ROY M. HOYA. 

